"Google search results for 'Trump News' shows only the viewing/reporting of Fake News Media," Trump wrote. "In other words, they have it RIGGED, for me & others, so that almost all stories & news is BAD. Fake CNN is prominent. Republican/Conservative & Fair Media is shut out,” Trump tweeted.

"There’s a massive problem with violent leftist rhetoric online that targets conservatives and their families; I’m all too familiar with its dangerous consequences," wrote Scalise, who was seriously injured during a shooting at a GOP baseball practice last year.

Twitter CEO Jack Dorsey is set to testify on the topic of alleged bias against conservatives before the House Energy and Commerce Committee on Sept. 5.

Dorsey will also appear alongside Facebook Chief Operating Officer Sheryl Sandberg and an expected representative from Google the same day for a Senate Intelligence Committee hearing on foreign manipulation of social media platforms to influence U.S. politics.